What should you examine to find the main idea in the paragraph?

Summer is a wonderful time to spend at West Beach. It is a beach with light- colored, soft sand. The coastline goes on for a long way and many people enjoy walking along it. Children like to play in the surf and walk along the rocks that are visible at low tide. This is a fun beach for people of all ages.

In this paragraph:   

Here is another example: 

The movie Apollo 13 was a blockbuster for the summer of 1995. It is an exciting story about space exploration. In the movie, the astronauts get in trouble while they are trying to return to Earth. People in the audience are on the edge of their seats waiting to see what happens. What makes it even more exciting is that it is a true story. 

In this paragraph: 

where is the